Is their any way to schedule a CRON Job, which triggers the script only on last Saturday of the month. Please advise.
One possibility might be to schedule the job to run every Saturday, but make execution of the actual command conditional on the month one week hence, ex.
0 9 * * 6 [ "$(date +\%b -d 'next week')" = "$(date +\%b)" ] || somecommand
Note that the %
character is special in crontabs, and needs to be escaped.